Negative Symptoms and Depression in Schizophrenia

Abstract

The question of the relationship between negative symptoms and the various signs and symptoms of depression is an important one given the current great interest in both negative and depressive symptoms in schizophrenia and the potential similarity between the two concepts (1). Table 1 highlights this conceptual similarity between common definitions of both negative symptoms and depression. As should be apparent, the behavioral signs that are generally considered as indicators of the negative symptom syndrome partially overlap with the broader group of signs and symptoms that are usually taken as indicative of a depressive syndrome. The potential consequences of this conceptual ambiguity are made more acute by the differences in theoretical hypotheses that are generally held for each syndrome. Table 1 also outlines some of these discrepancies between hypotheses concerning negative and depressive symptoms in schizophrenia. As can be seen, most hypotheses predict that negative symptoms will be associated with more severe characteristics, whereas depressive symptoms are usually predicted to be related to more benign characteristics. Given such disparate hypotheses and yet such similar concepts, it becomes crucial to know to what degree “negative” and “depressive” symptoms may be distinguishable among schizophrenic patients. The aim of the current research was therefore to examine the nature of this relationship among schizophrenic patients between negative symptoms and the various signs and symptoms of depression.